“Base layer” apparel conventionally refers to garments that are worn against the skin, often as inner garments such as underwear, T-shirts, and brassieres, beneath outerwear such as trousers, shirts/blouses, skirts, etc. Such garments are formed to have a soft touch, or hand, and among other things, provide support against the skin, and serve to absorb perspiration during normal daily activities. Most of these garments are made substantially of cotton, a natural fiber that is inexpensive and quite suitable for most wearers and most applications.
Unfortunately, however, base layer garments formed of conventional yarns and fabrics are not adequate for wear in occupations defined by potential hazardous exposures to sources of ignition, or high voltage electricity. While cotton base layer apparel may be treated to afford some flame-resistance, the chemical treatment on the cotton fibers degrades over the life of the garment through physical wear and laundering. This, of course, is unsatisfactory for base layer apparel for military personnel that is subjected to extreme wear conditions. Coupled with the constant risk in combat areas of bodily harm from the ignition of highly flammable materials such as gas and explosives, incendiary, or flame-producing munitions, something more is needed to personal protection.
While some flame-resistant yarns and fibers are now known for use in manufacturing apparel, these materials alone do not provide a satisfactory degree of comfort when formed into base layer apparel worn adjacent the skin. Most of these synthetic flame resistant materials also are generally hydrophobic, meaning that they lack an affinity to and absorbency for moisture and/or body perspiration.
What is needed is a fabric for base layer apparel that provides not only adequate, long-term, flame resistance, but that also is moisture absorbent and has a soft hand that is comfortable to the wearer under conditions such as high temperature and high humidity, and for extended periods.